Quality strings since 1956; Steel core, metal alloy or fibre winding; Warm, brilliant sound and durability; The “Classic” series standard strings; The A+D strings of the “Special” series are 0.01 mm thicker; The “Superior” strings are 0.02 mm thicker than “Special”; The “Silver Sound” G strings with flexible steel core and silver winding; D “Superior” ;String gauges/tension: ;dolce 1.00mm/14.4kp/31.7lbs;medium 1.01mm/14.7kp/32.3lbs;forte 1.02mm/15.1kp/33.2lbs;